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            <div class="highlight"><pre><span class="lineno">1</span><span></span><span class="kn">import</span> <span class="nn">torch</span>
<span class="lineno">2</span><span class="kn">import</span> <span class="nn">torch.nn</span> <span class="k">as</span> <span class="nn">nn</span>
<span class="lineno">3</span><span class="kn">from</span> <span class="nn">transformers</span> <span class="kn">import</span> <span class="n">AutoTokenizer</span>
<span class="lineno">4</span><span class="kn">from</span> <span class="nn">labml_nn.lora</span> <span class="kn">import</span> <span class="n">Linear</span><span class="p">,</span> <span class="n">Embedding</span>
<span class="lineno">5</span>
<span class="lineno">6</span><span class="n">tokenizer</span> <span class="o">=</span> <span class="n">AutoTokenizer</span><span class="o">.</span><span class="n">from_pretrained</span><span class="p">(</span><span class="s2">&quot;gpt2&quot;</span><span class="p">)</span>
<span class="lineno">7</span>
<span class="lineno">8</span><span class="n">config</span> <span class="o">=</span> <span class="p">{</span>
<span class="lineno">9</span>    <span class="s2">&quot;layer_norm_epsilon&quot;</span><span class="p">:</span> <span class="mf">1e-05</span><span class="p">,</span>
<span class="lineno">10</span>    <span class="s2">&quot;n_embd&quot;</span><span class="p">:</span> <span class="mi">768</span><span class="p">,</span>
<span class="lineno">11</span>    <span class="s2">&quot;n_head&quot;</span><span class="p">:</span> <span class="mi">12</span><span class="p">,</span>
<span class="lineno">12</span>    <span class="s2">&quot;n_layer&quot;</span><span class="p">:</span> <span class="mi">12</span><span class="p">,</span>
<span class="lineno">13</span>    <span class="s2">&quot;n_positions&quot;</span><span class="p">:</span> <span class="mi">1024</span><span class="p">,</span>
<span class="lineno">14</span>    <span class="s2">&quot;vocab_size&quot;</span><span class="p">:</span> <span class="mi">50257</span><span class="p">,</span>
<span class="lineno">15</span>    <span class="s2">&quot;device&quot;</span><span class="p">:</span> <span class="s2">&quot;cuda&quot;</span>
<span class="lineno">16</span><span class="p">}</span></pre></div>
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            <div class="highlight"><pre><span class="lineno">19</span><span class="k">class</span> <span class="nc">FFN</span><span class="p">(</span><span class="n">nn</span><span class="o">.</span><span class="n">Module</span><span class="p">):</span></pre></div>
        </div>
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    <div class='section' id='section-2'>
        <div class='docs'>
            <div class='section-link'>
                <a href='#section-2'>#</a>
            </div>
            
        </div>
        <div class='code'>
            <div class="highlight"><pre><span class="lineno">20</span>    <span class="k">def</span> <span class="fm">__init__</span><span class="p">(</span><span class="bp">self</span><span class="p">,</span> <span class="n">dim</span><span class="p">):</span>
<span class="lineno">21</span>        <span class="nb">super</span><span class="p">()</span><span class="o">.</span><span class="fm">__init__</span><span class="p">()</span>
<span class="lineno">22</span>        <span class="bp">self</span><span class="o">.</span><span class="n">c_fc</span> <span class="o">=</span> <span class="n">Linear</span><span class="p">(</span><span class="n">config</span><span class="p">[</span><span class="s1">&#39;n_embd&#39;</span><span class="p">],</span> <span class="n">dim</span><span class="p">,</span> <span class="n">r</span><span class="o">=</span><span class="mi">32</span><span class="p">,</span> <span class="n">bias</span><span class="o">=</span><span class="kc">True</span><span class="p">)</span>
<span class="lineno">23</span>        <span class="bp">self</span><span class="o">.</span><span class="n">c_proj</span> <span class="o">=</span> <span class="n">Linear</span><span class="p">(</span><span class="n">dim</span><span class="p">,</span> <span class="n">config</span><span class="p">[</span><span class="s1">&#39;n_embd&#39;</span><span class="p">],</span> <span class="n">r</span><span class="o">=</span><span class="mi">32</span><span class="p">,</span> <span class="n">bias</span><span class="o">=</span><span class="kc">True</span><span class="p">)</span>
<span class="lineno">24</span>        <span class="bp">self</span><span class="o">.</span><span class="n">act</span> <span class="o">=</span> <span class="n">nn</span><span class="o">.</span><span class="n">functional</span><span class="o">.</span><span class="n">gelu</span></pre></div>
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    <div class='section' id='section-3'>
        <div class='docs'>
            <div class='section-link'>
                <a href='#section-3'>#</a>
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        </div>
        <div class='code'>
            <div class="highlight"><pre><span class="lineno">26</span>    <span class="k">def</span> <span class="nf">forward</span><span class="p">(</span><span class="bp">self</span><span class="p">,</span> <span class="n">hidden_states</span><span class="p">):</span>
<span class="lineno">27</span>        <span class="n">hidden_states</span> <span class="o">=</span> <span class="bp">self</span><span class="o">.</span><span class="n">c_fc</span><span class="p">(</span><span class="n">hidden_states</span><span class="p">)</span>
<span class="lineno">28</span>        <span class="n">hidden_states</span> <span class="o">=</span> <span class="bp">self</span><span class="o">.</span><span class="n">act</span><span class="p">(</span><span class="n">hidden_states</span><span class="p">)</span>
<span class="lineno">29</span>        <span class="n">hidden_states</span> <span class="o">=</span> <span class="bp">self</span><span class="o">.</span><span class="n">c_proj</span><span class="p">(</span><span class="n">hidden_states</span><span class="p">)</span>
<span class="lineno">30</span>        <span class="k">return</span> <span class="n">hidden_states</span></pre></div>
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    </div>
    <div class='section' id='section-4'>
        <div class='docs'>
            <div class='section-link'>
                <a href='#section-4'>#</a>
            </div>
            
        </div>
        <div class='code'>
            <div class="highlight"><pre><span class="lineno">33</span><span class="k">class</span> <span class="nc">MultiHeadAttention</span><span class="p">(</span><span class="n">nn</span><span class="o">.</span><span class="n">Module</span><span class="p">):</span></pre></div>
        </div>
    </div>
    <div class='section' id='section-5'>
        <div class='docs'>
            <div class='section-link'>
                <a href='#section-5'>#</a>
            </div>
            
        </div>
        <div class='code'>
            <div class="highlight"><pre><span class="lineno">34</span>    <span class="k">def</span> <span class="fm">__init__</span><span class="p">(</span><span class="bp">self</span><span class="p">):</span>
<span class="lineno">35</span>        <span class="nb">super</span><span class="p">()</span><span class="o">.</span><span class="fm">__init__</span><span class="p">()</span>
<span class="lineno">36</span>        <span class="bp">self</span><span class="o">.</span><span class="n">embed_dim</span> <span class="o">=</span> <span class="n">config</span><span class="p">[</span><span class="s1">&#39;n_embd&#39;</span><span class="p">]</span>
<span class="lineno">37</span>        <span class="bp">self</span><span class="o">.</span><span class="n">num_heads</span> <span class="o">=</span> <span class="n">config</span><span class="p">[</span><span class="s1">&#39;n_head&#39;</span><span class="p">]</span>
<span class="lineno">38</span>        <span class="bp">self</span><span class="o">.</span><span class="n">head_dim</span> <span class="o">=</span> <span class="bp">self</span><span class="o">.</span><span class="n">embed_dim</span> <span class="o">//</span> <span class="bp">self</span><span class="o">.</span><span class="n">num_heads</span>
<span class="lineno">39</span>        <span class="bp">self</span><span class="o">.</span><span class="n">split_size</span> <span class="o">=</span> <span class="bp">self</span><span class="o">.</span><span class="n">embed_dim</span>
<span class="lineno">40</span>
<span class="lineno">41</span>        <span class="bp">self</span><span class="o">.</span><span class="n">c_att</span> <span class="o">=</span> <span class="n">Linear</span><span class="p">(</span><span class="n">config</span><span class="p">[</span><span class="s1">&#39;n_embd&#39;</span><span class="p">],</span> <span class="n">config</span><span class="p">[</span><span class="s1">&#39;n_embd&#39;</span><span class="p">]</span> <span class="o">*</span> <span class="mi">3</span><span class="p">,</span> <span class="n">r</span><span class="o">=</span><span class="mi">32</span><span class="p">,</span> <span class="n">bias</span><span class="o">=</span><span class="kc">True</span><span class="p">)</span>
<span class="lineno">42</span>        <span class="bp">self</span><span class="o">.</span><span class="n">c_proj</span> <span class="o">=</span> <span class="n">Linear</span><span class="p">(</span><span class="n">config</span><span class="p">[</span><span class="s1">&#39;n_embd&#39;</span><span class="p">],</span> <span class="n">config</span><span class="p">[</span><span class="s1">&#39;n_embd&#39;</span><span class="p">],</span> <span class="n">r</span><span class="o">=</span><span class="mi">32</span><span class="p">,</span> <span class="n">bias</span><span class="o">=</span><span class="kc">True</span><span class="p">)</span></pre></div>
        </div>
    </div>
    <div class='section' id='section-6'>
        <div class='docs doc-strings'>
            <div class='section-link'>
                <a href='#section-6'>#</a>
            </div>
            <p> Splits hidden_size dim into attn_head_size and num_heads</p>

        </div>
        <div class='code'>
            <div class="highlight"><pre><span class="lineno">44</span>    <span class="k">def</span> <span class="nf">_split_heads</span><span class="p">(</span><span class="bp">self</span><span class="p">,</span> <span class="n">tensor</span><span class="p">,</span> <span class="n">num_heads</span><span class="p">,</span> <span class="n">attn_head_size</span><span class="p">):</span></pre></div>
        </div>
    </div>
    <div class='section' id='section-7'>
        <div class='docs'>
            <div class='section-link'>
                <a href='#section-7'>#</a>
            </div>
            
        </div>
        <div class='code'>
            <div class="highlight"><pre><span class="lineno">48</span>        <span class="n">new_shape</span> <span class="o">=</span> <span class="n">tensor</span><span class="o">.</span><span class="n">size</span><span class="p">()[:</span><span class="o">-</span><span class="mi">1</span><span class="p">]</span> <span class="o">+</span> <span class="p">(</span><span class="n">num_heads</span><span class="p">,</span> <span class="n">attn_head_size</span><span class="p">)</span>
<span class="lineno">49</span>        <span class="n">tensor</span> <span class="o">=</span> <span class="n">tensor</span><span class="o">.</span><span class="n">view</span><span class="p">(</span><span class="n">new_shape</span><span class="p">)</span>
<span class="lineno">50</span>        <span class="k">return</span> <span class="n">tensor</span><span class="o">.</span><span class="n">permute</span><span class="p">(</span><span class="mi">0</span><span class="p">,</span> <span class="mi">2</span><span class="p">,</span> <span class="mi">1</span><span class="p">,</span> <span class="mi">3</span><span class="p">)</span>  <span class="c1"># (batch, head, seq_length, head_features)</span></pre></div>
        </div>
    </div>
    <div class='section' id='section-8'>
        <div class='docs'>
            <div class='section-link'>
                <a href='#section-8'>#</a>
            </div>
            
        </div>
        <div class='code'>
            <div class="highlight"><pre><span class="lineno">52</span>    <span class="k">def</span> <span class="nf">forward</span><span class="p">(</span><span class="bp">self</span><span class="p">,</span> <span class="n">hidden_states</span><span class="p">):</span>
<span class="lineno">53</span>        <span class="n">batch_size</span><span class="p">,</span> <span class="n">seq_length</span><span class="p">,</span> <span class="n">_</span> <span class="o">=</span> <span class="n">hidden_states</span><span class="o">.</span><span class="n">size</span><span class="p">()</span>
<span class="lineno">54</span>
<span class="lineno">55</span>        <span class="n">query</span><span class="p">,</span> <span class="n">key</span><span class="p">,</span> <span class="n">value</span> <span class="o">=</span> <span class="bp">self</span><span class="o">.</span><span class="n">c_att</span><span class="p">(</span><span class="n">hidden_states</span><span class="p">)</span><span class="o">.</span><span class="n">split</span><span class="p">(</span><span class="bp">self</span><span class="o">.</span><span class="n">split_size</span><span class="p">,</span> <span class="n">dim</span><span class="o">=</span><span class="mi">2</span><span class="p">)</span>
<span class="lineno">56</span>
<span class="lineno">57</span>        <span class="n">query</span> <span class="o">=</span> <span class="bp">self</span><span class="o">.</span><span class="n">_split_heads</span><span class="p">(</span><span class="n">query</span><span class="p">,</span> <span class="bp">self</span><span class="o">.</span><span class="n">num_heads</span><span class="p">,</span> <span class="bp">self</span><span class="o">.</span><span class="n">head_dim</span><span class="p">)</span>
<span class="lineno">58</span>        <span class="n">key</span> <span class="o">=</span> <span class="bp">self</span><span class="o">.</span><span class="n">_split_heads</span><span class="p">(</span><span class="n">key</span><span class="p">,</span> <span class="bp">self</span><span class="o">.</span><span class="n">num_heads</span><span class="p">,</span> <span class="bp">self</span><span class="o">.</span><span class="n">head_dim</span><span class="p">)</span>
<span class="lineno">59</span>        <span class="n">value</span> <span class="o">=</span> <span class="bp">self</span><span class="o">.</span><span class="n">_split_heads</span><span class="p">(</span><span class="n">value</span><span class="p">,</span> <span class="bp">self</span><span class="o">.</span><span class="n">num_heads</span><span class="p">,</span> <span class="bp">self</span><span class="o">.</span><span class="n">head_dim</span><span class="p">)</span>
<span class="lineno">60</span>
<span class="lineno">61</span>        <span class="n">attn_output</span> <span class="o">=</span> <span class="n">torch</span><span class="o">.</span><span class="n">nn</span><span class="o">.</span><span class="n">functional</span><span class="o">.</span><span class="n">scaled_dot_product_attention</span><span class="p">(</span>
<span class="lineno">62</span>            <span class="n">query</span><span class="p">,</span>
<span class="lineno">63</span>            <span class="n">key</span><span class="p">,</span>
<span class="lineno">64</span>            <span class="n">value</span><span class="p">,</span>
<span class="lineno">65</span>            <span class="n">attn_mask</span><span class="o">=</span><span class="kc">None</span><span class="p">,</span>
<span class="lineno">66</span>            <span class="n">dropout_p</span><span class="o">=</span><span class="mf">0.0</span><span class="p">,</span>
<span class="lineno">67</span>            <span class="n">is_causal</span><span class="o">=</span><span class="kc">True</span><span class="p">,</span>  <span class="c1"># for the triangular mask</span>
<span class="lineno">68</span>        <span class="p">)</span>
<span class="lineno">69</span>
<span class="lineno">70</span>        <span class="n">attn_output</span> <span class="o">=</span> <span class="n">attn_output</span><span class="o">.</span><span class="n">transpose</span><span class="p">(</span><span class="mi">1</span><span class="p">,</span> <span class="mi">2</span><span class="p">)</span><span class="o">.</span><span class="n">contiguous</span><span class="p">()</span>
<span class="lineno">71</span>        <span class="n">attn_output</span> <span class="o">=</span> <span class="n">attn_output</span><span class="o">.</span><span class="n">view</span><span class="p">(</span><span class="n">batch_size</span><span class="p">,</span> <span class="n">seq_length</span><span class="p">,</span> <span class="bp">self</span><span class="o">.</span><span class="n">embed_dim</span><span class="p">)</span>
<span class="lineno">72</span>
<span class="lineno">73</span>        <span class="n">attn_output</span> <span class="o">=</span> <span class="bp">self</span><span class="o">.</span><span class="n">c_proj</span><span class="p">(</span><span class="n">attn_output</span><span class="p">)</span>
<span class="lineno">74</span>
<span class="lineno">75</span>        <span class="k">return</span> <span class="n">attn_output</span></pre></div>
        </div>
    </div>
    <div class='section' id='section-9'>
        <div class='docs'>
            <div class='section-link'>
                <a href='#section-9'>#</a>
            </div>
            
        </div>
        <div class='code'>
            <div class="highlight"><pre><span class="lineno">78</span><span class="k">class</span> <span class="nc">Block</span><span class="p">(</span><span class="n">nn</span><span class="o">.</span><span class="n">Module</span><span class="p">):</span></pre></div>
        </div>
    </div>
    <div class='section' id='section-10'>
        <div class='docs'>
            <div class='section-link'>
                <a href='#section-10'>#</a>
            </div>
            
        </div>
        <div class='code'>
            <div class="highlight"><pre><span class="lineno">79</span>    <span class="k">def</span> <span class="fm">__init__</span><span class="p">(</span><span class="bp">self</span><span class="p">):</span>
<span class="lineno">80</span>        <span class="nb">super</span><span class="p">()</span><span class="o">.</span><span class="fm">__init__</span><span class="p">()</span>
<span class="lineno">81</span>        <span class="bp">self</span><span class="o">.</span><span class="n">pre_norm</span> <span class="o">=</span> <span class="n">nn</span><span class="o">.</span><span class="n">LayerNorm</span><span class="p">(</span><span class="n">config</span><span class="p">[</span><span class="s1">&#39;n_embd&#39;</span><span class="p">],</span> <span class="n">eps</span><span class="o">=</span><span class="n">config</span><span class="p">[</span><span class="s1">&#39;layer_norm_epsilon&#39;</span><span class="p">])</span>
<span class="lineno">82</span>        <span class="bp">self</span><span class="o">.</span><span class="n">attn</span> <span class="o">=</span> <span class="n">MultiHeadAttention</span><span class="p">()</span>
<span class="lineno">83</span>        <span class="bp">self</span><span class="o">.</span><span class="n">post_norm</span> <span class="o">=</span> <span class="n">nn</span><span class="o">.</span><span class="n">LayerNorm</span><span class="p">(</span><span class="n">config</span><span class="p">[</span><span class="s1">&#39;n_embd&#39;</span><span class="p">],</span> <span class="n">eps</span><span class="o">=</span><span class="n">config</span><span class="p">[</span><span class="s1">&#39;layer_norm_epsilon&#39;</span><span class="p">])</span>
<span class="lineno">84</span>        <span class="bp">self</span><span class="o">.</span><span class="n">ffn</span> <span class="o">=</span> <span class="n">FFN</span><span class="p">(</span><span class="n">config</span><span class="p">[</span><span class="s1">&#39;n_embd&#39;</span><span class="p">]</span> <span class="o">*</span> <span class="mi">4</span><span class="p">)</span></pre></div>
        </div>
    </div>
    <div class='section' id='section-11'>
        <div class='docs'>
            <div class='section-link'>
                <a href='#section-11'>#</a>
            </div>
            
        </div>
        <div class='code'>
            <div class="highlight"><pre><span class="lineno">86</span>    <span class="k">def</span> <span class="nf">forward</span><span class="p">(</span><span class="bp">self</span><span class="p">,</span> <span class="n">hidden_states</span><span class="p">):</span>
<span class="lineno">87</span>        <span class="n">residual</span> <span class="o">=</span> <span class="n">hidden_states</span>
<span class="lineno">88</span>        <span class="n">hidden_states</span> <span class="o">=</span> <span class="bp">self</span><span class="o">.</span><span class="n">pre_norm</span><span class="p">(</span><span class="n">hidden_states</span><span class="p">)</span>
<span class="lineno">89</span>
<span class="lineno">90</span>        <span class="n">attn_output</span> <span class="o">=</span> <span class="bp">self</span><span class="o">.</span><span class="n">attn</span><span class="p">(</span><span class="n">hidden_states</span><span class="p">)</span>
<span class="lineno">91</span>
<span class="lineno">92</span>        <span class="n">hidden_states</span> <span class="o">=</span> <span class="n">attn_output</span> <span class="o">+</span> <span class="n">residual</span>
<span class="lineno">93</span>        <span class="n">residual</span> <span class="o">=</span> <span class="n">hidden_states</span>
<span class="lineno">94</span>        <span class="n">hidden_states</span> <span class="o">=</span> <span class="bp">self</span><span class="o">.</span><span class="n">post_norm</span><span class="p">(</span><span class="n">hidden_states</span><span class="p">)</span>
<span class="lineno">95</span>        <span class="n">feed_forward_output</span> <span class="o">=</span> <span class="bp">self</span><span class="o">.</span><span class="n">ffn</span><span class="p">(</span><span class="n">hidden_states</span><span class="p">)</span>
<span class="lineno">96</span>        <span class="n">hidden_states</span> <span class="o">=</span> <span class="n">feed_forward_output</span> <span class="o">+</span> <span class="n">residual</span>
<span class="lineno">97</span>
<span class="lineno">98</span>        <span class="k">return</span> <span class="n">hidden_states</span></pre></div>
        </div>
    </div>
    <div class='section' id='section-12'>
        <div class='docs'>
            <div class='section-link'>
                <a href='#section-12'>#</a>
            </div>
            
        </div>
        <div class='code'>
            <div class="highlight"><pre><span class="lineno">101</span><span class="k">class</span> <span class="nc">GPTModel</span><span class="p">(</span><span class="n">nn</span><span class="o">.</span><span class="n">Module</span><span class="p">):</span></pre></div>
        </div>
    </div>
    <div class='section' id='section-13'>
        <div class='docs'>
            <div class='section-link'>
                <a href='#section-13'>#</a>
            </div>
            
        </div>
        <div class='code'>
            <div class="highlight"><pre><span class="lineno">102</span>    <span class="k">def</span> <span class="fm">__init__</span><span class="p">(</span><span class="bp">self</span><span class="p">):</span>
<span class="lineno">103</span>        <span class="nb">super</span><span class="p">()</span><span class="o">.</span><span class="fm">__init__</span><span class="p">()</span>
<span class="lineno">104</span>
<span class="lineno">105</span>        <span class="bp">self</span><span class="o">.</span><span class="n">token_embedding</span> <span class="o">=</span> <span class="n">Embedding</span><span class="p">(</span><span class="n">config</span><span class="p">[</span><span class="s1">&#39;vocab_size&#39;</span><span class="p">],</span> <span class="n">config</span><span class="p">[</span><span class="s1">&#39;n_embd&#39;</span><span class="p">],</span> <span class="n">r</span><span class="o">=</span><span class="mi">32</span><span class="p">)</span>
<span class="lineno">106</span>        <span class="bp">self</span><span class="o">.</span><span class="n">position_embedding</span> <span class="o">=</span> <span class="n">Embedding</span><span class="p">(</span><span class="n">config</span><span class="p">[</span><span class="s1">&#39;n_positions&#39;</span><span class="p">],</span> <span class="n">config</span><span class="p">[</span><span class="s1">&#39;n_embd&#39;</span><span class="p">],</span> <span class="n">r</span><span class="o">=</span><span class="mi">32</span><span class="p">)</span>
<span class="lineno">107</span>
<span class="lineno">108</span>        <span class="bp">self</span><span class="o">.</span><span class="n">blocks</span> <span class="o">=</span> <span class="n">nn</span><span class="o">.</span><span class="n">ModuleList</span><span class="p">([</span><span class="n">Block</span><span class="p">()</span> <span class="k">for</span> <span class="n">_</span> <span class="ow">in</span> <span class="nb">range</span><span class="p">(</span><span class="n">config</span><span class="p">[</span><span class="s1">&#39;n_layer&#39;</span><span class="p">])])</span>
<span class="lineno">109</span>
<span class="lineno">110</span>        <span class="bp">self</span><span class="o">.</span><span class="n">final_norm</span> <span class="o">=</span> <span class="n">nn</span><span class="o">.</span><span class="n">LayerNorm</span><span class="p">(</span><span class="n">config</span><span class="p">[</span><span class="s1">&#39;n_embd&#39;</span><span class="p">],</span> <span class="n">eps</span><span class="o">=</span><span class="n">config</span><span class="p">[</span><span class="s1">&#39;layer_norm_epsilon&#39;</span><span class="p">])</span>
<span class="lineno">111</span>
<span class="lineno">112</span>        <span class="bp">self</span><span class="o">.</span><span class="n">lm_head</span> <span class="o">=</span> <span class="n">Linear</span><span class="p">(</span><span class="n">config</span><span class="p">[</span><span class="s1">&#39;n_embd&#39;</span><span class="p">],</span> <span class="n">config</span><span class="p">[</span><span class="s1">&#39;vocab_size&#39;</span><span class="p">],</span> <span class="n">r</span><span class="o">=</span><span class="mi">32</span><span class="p">,</span> <span class="n">bias</span><span class="o">=</span><span class="kc">False</span><span class="p">)</span></pre></div>
        </div>
    </div>
    <div class='section' id='section-14'>
        <div class='docs'>
            <div class='section-link'>
                <a href='#section-14'>#</a>
            </div>
            
        </div>
        <div class='code'>
            <div class="highlight"><pre><span class="lineno">114</span>    <span class="k">def</span> <span class="nf">forward</span><span class="p">(</span><span class="bp">self</span><span class="p">,</span> <span class="n">input_ids</span><span class="p">):</span>
<span class="lineno">115</span>        <span class="n">batch_size</span><span class="p">,</span> <span class="n">input_shape</span> <span class="o">=</span> <span class="n">input_ids</span><span class="o">.</span><span class="n">size</span><span class="p">()</span>
<span class="lineno">116</span>
<span class="lineno">117</span>        <span class="n">token_embeddings</span> <span class="o">=</span> <span class="bp">self</span><span class="o">.</span><span class="n">token_embedding</span><span class="p">(</span><span class="n">input_ids</span><span class="p">)</span>  <span class="c1"># B T C</span>
<span class="lineno">118</span>        <span class="n">position_ids</span> <span class="o">=</span> <span class="n">torch</span><span class="o">.</span><span class="n">arange</span><span class="p">(</span><span class="n">input_shape</span><span class="p">,</span> <span class="n">device</span><span class="o">=</span><span class="n">config</span><span class="p">[</span><span class="s1">&#39;device&#39;</span><span class="p">])</span>  <span class="c1"># T C</span>
<span class="lineno">119</span>        <span class="n">position_embeddings</span> <span class="o">=</span> <span class="bp">self</span><span class="o">.</span><span class="n">position_embedding</span><span class="p">(</span><span class="n">position_ids</span><span class="p">)</span>  <span class="c1"># B T C</span>
<span class="lineno">120</span>
<span class="lineno">121</span>        <span class="n">hidden_states</span> <span class="o">=</span> <span class="n">token_embeddings</span> <span class="o">+</span> <span class="n">position_embeddings</span>
<span class="lineno">122</span>
<span class="lineno">123</span>        <span class="k">for</span> <span class="n">block</span> <span class="ow">in</span> <span class="bp">self</span><span class="o">.</span><span class="n">blocks</span><span class="p">:</span>
<span class="lineno">124</span>            <span class="n">hidden_states</span> <span class="o">=</span> <span class="n">block</span><span class="p">(</span><span class="n">hidden_states</span><span class="p">)</span>
<span class="lineno">125</span>
<span class="lineno">126</span>        <span class="n">hidden_states</span> <span class="o">=</span> <span class="bp">self</span><span class="o">.</span><span class="n">final_norm</span><span class="p">(</span><span class="n">hidden_states</span><span class="p">)</span>
<span class="lineno">127</span>
<span class="lineno">128</span>        <span class="n">logits</span> <span class="o">=</span> <span class="bp">self</span><span class="o">.</span><span class="n">lm_head</span><span class="p">(</span><span class="n">hidden_states</span><span class="p">)</span>
<span class="lineno">129</span>
<span class="lineno">130</span>        <span class="k">return</span> <span class="n">logits</span></pre></div>
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